Fibrous proteins (also known as scleroproteins) are generally inert and insoluble in water. Fibrous proteins form long protein filaments shaped like rods or wires. They are structural or storage proteins. Fibrous proteins include keratin, collagen, elastin and fibroin.
Wool is a keratin protein fibre and is produced by various animals including sheep, goats, camels and rabbits. The fibre structure comprises a cuticle, cortex, and medulla, although fine wools may lack the medulla.
Wool can be readily dissolved in strong alkali solutions. Treating wool with a solution of hot concentrated sodium hydroxide results in complete hydrolysis of the disulfide and peptide bonds, and the wool is eventually broken down into its constituent amino acids.
The diameter of sheep wool typically ranges from about 10 microns to about 45 microns. Fibre diameter is an important characteristic of wool in relation to its quality and price. Finer wools are softer and suitable for use in garment manufacturing. There are a limited number of consumer applications remaining for stronger wool types such as flooring, bedding, upholstery, and hand knitting yarns.
Previous attempts to reprocess coarse wool to fine wool have largely failed because of the cost of the solubilisation step.
Accordingly, it is an object of the present invention to go some way to avoiding the above disadvantages; and/or to at least provide the public with a useful choice.
Other objects of the invention may become apparent from the following description which is given by way of example only.